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Evaluation of PCV21 Vaccination Among PPSV23-experienced, Immunocompromised Elderly Veterans

Evaluation of PCV21 Vaccination Among PPSV23-experienced, Immunocompromised Elderly Veterans

Status
Not yet recruiting
Phases
Phase 4
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT06271681
Enrollment
45
Registered
2024-02-22
Start date
2026-01-01
Completion date
2027-06-01
Last updated
2025-08-14

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Immunosuppression, Pneumococcal Vaccines

Keywords

immunosuppression, pneumococcal vaccines

Brief summary

The investigators will evaluate the immune response of immunocompromised adults, who have previously received at least 1 dose of 23-valent pneumococcal polysaccharide vaccine, to the booster with of 21-valent pneumococcal conjugate vaccine . Immune response will be assessed by opsonophagocytic assay reactivity.

Detailed description

Recommendations for optimal vaccination strategies in immunocompromised patients has been limited. Strategies focused on utilizing a conjugate vaccine alone, as either initial vaccination or booster dosing, have not demonstrated significant increased antibody expression in immunocompromised patients\[7\]. Strategies where immunocompromised patients were vaccinated with a conjugate vaccine followed by polysaccharide vaccine have demonstrated that 50% of individuals achieve functional antibodies\[7\]. Since improved antibody response in naive patients has been seen in combination vaccination, we aim to test this strategy for boosting in previously vaccinated immunocompromised patients. The 15 valent Pneumococcal Conjugate Vaccine (PCV15) is available for use in adults and contains S. Pneumoniae serotypes 1, 3, 4, 6A, 7F, 9V, 14, 18C, 19A, 19F, 22F, 23F and 33F \[5\]. In this study we postulate that booster dosing with PCV21 in immunocompromised adults who are at least 5 years from receipt of PPSV23 will elicit a strong immune response represented by change in serotype specific OPA GMT from baseline to 4 weeks post booster vaccine completion. We will specifically evaluate the change in pneumococcal opsonophagocytic activity at baseline to 6 months (Pn-OPA) for S. Pneumoniae serotypes 3, 6A, 15A, 19A, 20A, 23A, 31, 35B, 9n, 11A, and 22F. These specific serotypes have been selected due to current disease burden trends, to address current gaps in data, and have been identified as the most relevant for PCV development underway.

Interventions

DRUG21-valent pneumococcal conjugate vaccine

FDA approved pneumococcal vaccines 21 valent conjugate vaccine administered at enrollment

Sponsors

Merck Sharp & Dohme LLC
CollaboratorINDUSTRY
VA Sierra Nevada Health Care System
Lead SponsorFED

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Healthy volunteers
No

Inclusion criteria

* Subject meets the CDC definition of an immunocompromising condition o chronic renal failure, congenital or acquired asplenia, generalized malignancy, HIV infection, Hodgkin disease, iatrogenic immunosuppression, leukemia, lymphoma, multiple myeloma, nephrotic syndrome, sickle cell disease or other hemoglobinopathies, and solid organ transplant. * Have received at least 1 dose of PPSV23

Exclusion criteria

* Less than 5 years since last receipt of PPSV23 validated to patient medical record and Immunize Nevada Website * Previous administration of PCV20 * Previous administration of PCV13 * Previous administration of PCV15 * Less than 14 days since administration of any COVID19 vaccination * Previous history of Invasive Pneumococcal Disease (IPD) * Antibiotic treatment within the previous 90 days

Design outcomes

Primary

MeasureTime frameDescription
Change in opsonophagocytic assay (OPA) geometric mean titers (GMT)24 monthsEvaluation of the change fold increase in S. Pneumonia OPA GMT from baseline to 24 weeks after the administration of a pneumococcal vaccine booster series consisting of PCV15 followed by PPSV23 8 weeks later for S. Pneumoniae serotypes 1, 3, 4, 6A, 7F, 9V, 14, 18C, 19A, 19F, 22F, 23F and 33F

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026